1. Field
The following description relates to a storage system and a method of adjusting a spare memory space in the storage system.
2. Description of Related Art
A method (over-provisioning method) includes using a part of a physical memory space as a spare memory space in a storage device, such as a flash memory, and using another part of the physical memory space as an available memory space in the storage device that can be actually used by a user. The spare memory space can help improve performance of the storage device and increase a life expectancy of the storage device.
For example, with respect to a flash memory, there are limitations on a number of writes and erases, and overwriting is impossible. Accordingly, when an overwriting request is received, data should be recorded after erasing data recorded in a corresponding page, and therefore, performance degradation may occur when a writing operation is continuously performed when there is a shortage of empty space.
Therefore, the spare memory space is ensured in advance, and when the overwriting request is received, data is recorded in the spare memory space, a logical memory address is updated, and unnecessary data is deleted later. This may improve the performance and increase the life expectancy by preventing writing and erasing operations from being concentrated on a specific block. Meanwhile, an effect may be increased by increasing a size of the spare memory space, but a size of the available memory space is reduced when the spare memory space is increased. Thus, there is a limitation on the size of the spare memory space.